<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>CSS盒子模型</title>
    <link rel="stylesheet" href="./styles/css03_box.css">
</head>
<body>
    <h1>CSS盒子模型</h1>
    <p>块级盒子</p>
    <ul>
        <li>选项</li>
    </ul>
    <a href="">内联</a><span>内联span</span><img src="" alt="图片">
    <div class="box">标准盒子模型</div>
    <div class="box alternate">替代盒子模型</div>

    <div class="container">
        <div class="row">外边距</div>
        <div class="row row_center">外边距</div>
        <div class="row">外边距</div>
    </div>

    <input class="input_username" type="text" placeholder="请输入用户名">

    <div class="container2">内边距</div>

    <ul class="menu">
        <li>菜单项1</li>
        <li>菜单项2</li>
        <li>菜单项3</li>
    </ul>
    <br><br><br><br><br><br><br><br><br><br>
</body>
</html>